Firstly, I want to say, P3D is used for training and learning, So Hardware cost can be avoid, that's too low compare to the TCO.
We may have multi-GPU, multi-CPU, many RAM over 32GB even 64GB and even more. So I think multi-GPU, multi-threads, more RAM utilize should be supported, also DirectX upgrade to DX12 or Vulkan for cross-plateform is a good choice.
Secondly, with the stronger hardware and supported firmware, more realistic and immerse feelings are important too.
Thirdly, I think we can add an useful data analyzer which can analyzing the data for takeoff, landing, ect.
Above are my suggestions, Hope to be considered.
Yours, Sincerely!